package site.hugboy.reggie.filter;

import com.alibaba.fastjson.JSON;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;
import site.hugboy.reggie.common.BaseContext;
import site.hugboy.reggie.common.R;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否已经登录
 */
@Slf4j
@WebFilter(filterName = "loginCheckFilter", urlPatterns = "/*")
public class LoginCheckFilter implements Filter {
    //路径匹配器
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();


    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest req = (HttpServletRequest) servletRequest;
        HttpServletResponse res = (HttpServletResponse) servletResponse;
        log.info("拦截到了：{}........", req.getRequestURI());
        //过滤器具体的处理逻辑如下：
        //1、获取本次请求的URI
        String URI = req.getRequestURI();
        //   定义不需要拦截的
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**"
        };
        //2、判断本次请求是否需要处理
        boolean check = check(urls, URI);
        log.info("是否需要处理：{}", !check);
        //3、如果不需要处理，则直接放行
        if(check){
            filterChain.doFilter(req, res);
            return;
        }
        //4、判断登录状态，如果已登录，则直接放行
        if(req.getSession().getAttribute("employee") != null){
            log.info("用户已经登录，ID: {}", req.getSession().getAttribute("employee"));
            log.info("处理结果：放行............");
            // 保存id
            Long empId = (Long) req.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(req, res);
            return;
        }
        //5、如果未登录则返回未登录结果
        log.info("用户未登录.");
        log.info("处理结果：拦截到登录页面............");
        res.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;

    }

    /**
     * 路径匹配，check是否需要放行
     *
     * @param urls
     * @param URI
     * @return
     */
    public boolean check(String[] urls, String URI) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, URI);
            if (match) {
                return true;
            }
        }
        return false;
    }
}
